Quantitative Determination of Metal Center Coordination Numbers in Resin‐Based Supported Catalysts via CO₂ Adsorption

ABSTRACT A novel method was described for quantitatively determining the metal centers' average coordination numbers in as‐prepared supported metal catalysts using polyamine‐modified resin carriers via CO 2 adsorption. Using porous resin (PS) and pentaethylenehexamine (PEHA) as starting materials, a new polyamine‐modified resin carrier PS‐PEHA was obtained to anchor various metals (Cu, Pd, Co, Ni, and Zn), thereby preparing a range of supported catalysts. The structures of the metal catalysts were characterized through FT‐IR, XPS, SEM, EDS, BET, and ICP‐OES. DVS was employed to study the carrier and catalyst performance of CO 2 adsorption. The average coordination numbers of the metal centers were quantitatively determined based on their differences in CO 2 adsorption capacities. The coordination numbers determined were Co (3.5), Ni (3.5), Pd (4.8), Zn (3.6), and Cu (5.9).